March 2008

Slide 1

doc.: IEEE 802.15-<160r1>

Submission

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

Submission Title: [PHY considerations for low power body area networks (BAN)]Date Submitted: [March 17, 2008]Source: [Zhanfeng Jia, Jason Ellis and Amal Ekbal] Company [Qualcomm, Inc.]Address [5775 Morehouse Drive, San Diego, CA 92121]Voice:[+1-858-845-6353], E-Mail:[jason.ellis@qualcomm.com]

Abstract: [This document presents an option for 802.15.6 PHY frequency band]

Purpose: [To promote a discussion of PHY frequency band options available for 802.15.6]

Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

March 2008

Slide 2

doc.: IEEE 802.15-<160r1>

Submission

PHY Considerations for Low Power Body Area Networks (BANs)

Draft Contribution for March 2008 IEEE 802.15.6 Meeting

Jason EllisAmal Ekbal

Zhanfeng Jia

March 2008

Slide 3

doc.: IEEE 802.15-<160r1>

Submission

Key Points

• Unlicensed Spectrum

• Technology Benefits

• Initial Propagation Results

• Low Cost Antenna Solutions

March 2008

Slide 4

doc.: IEEE 802.15-<160r1>

Submission

Available Unlicensed Spectrum• ISM: 900MHz and 2.4GHz

– Very congested• WiFi• Bluetooth• Zigbee• Cordless Phones• Microwave Overs• Misc

• UNII: 5GHz – less congested• Some WiFI (802.11a, possible small amount of 11g)• Cordless Phones• Misc

• UWB: 3.1-10.6GHz– Newly unlicensed globally, – WiMedia (Wireless USB and Bluetooth 3.0)– Unique properties for communication

• 60GHz– Globally unlicensed spectrum– Basis for new very high speed and wireless video standards

March 2008

Slide 5

doc.: IEEE 802.15-<160r1>

Submission

The global unlicensed spectrum “window”

• Regulatory Status– US UWB legal 3.1-10.6 GHz– EU has legalized 6-8.5GHz – Japan has legalized 7.25-10.25GHz for high data rate (>50Mbps)

• Regulators still working on lower data rate

• 7.25-8.50 GHz is a globally available “window” of spectrum

March 2008

Slide 6

doc.: IEEE 802.15-<160r1>

Submission

A closer look at 7.25-8.5 GHz Benefits• Worldwide unlicensed spectrum

• Low in-band interference compared with ISM and UNII

• Small antenna sizes lead to small form factors– Doubling frequency halves the antenna in each dimension

• Good spatial reuse for dense deployments (e.g. hospitals, cars, buses,)

• Multipath capture – – good for use in hospital, ship, container environments

• Body area propagation is acceptable

• No DAA requirements (detecting victim receivers) on low power BAN technologies

• Low complexity, implementable in standard CMOS processes

March 2008

Slide 7

doc.: IEEE 802.15-<160r1>

Submission

High Frequency Antennas can be Low Cost

• $0.02 Antennas (inexpensive)• Very small• Omni directional antenna• Perform well in 7.25-8.5GHz

Source: Antenna picture and gain plots from PUBs, http://timederivative.com/pubs.html

March 2008

Slide 8

doc.: IEEE 802.15-<160r1>

Submission

Initial Path Loss Measurements

Pulse Generator

Pulse Shaper

BPF PA

RF Coupler

RF Coupler

BPFLNA

DSO

Post

Processing

-10 dB

Signal Generator

for Blockers / Jammers

-10 dB

Channel

Transmit Chain

Receive Chain

Capture T

rigger

Picosecond 4015DPicosecond 4015D-

RPH Narda 4226-10

Ciao WirelessCA611-441

Narda 4226-10

Ciao WirelessCA611-441

Tektronix TDS6124C

• Measurements with off-the-shelf test-equipment to send and receive impulse waveforms at 7.25 to 9 GHz

• Digital Storage Oscilliscope (DSO) captures Tx and Rx waveforms

• Signals demodulated in Matlab

• Preliminary measurements for (see following slides)

• line-of-sight, 2’

• pocket-to-ear

• Thru-wall and thru-door

March 2008

Slide 9

doc.: IEEE 802.15-<160r1>

Submission

Typical Channel Measurements -1Line-of-Sight, 2 feet

Ear to Opposite Pants pocket

2.5ns 5ns

Ep/N0 = 34dBEp/N0 = 28dB

Path loss = 49dBPath loss = 55dB

March 2008

Slide 10

doc.: IEEE 802.15-<160r1>

Submission

Typical Channel Measurements -2Thru-Wall, 4.5’

Thru-door, 4.2’

5ns

5ns

Through interior office wallPath loss = 56dB

Through interior office doorPath loss = 56dB

Ep/N0 = 27dB

Ep/N0 = 27dB

March 2008

Slide 11

doc.: IEEE 802.15-<160r1>

Submission

Typical Channel Measurements: Pocket to Ear

Location

Pant’s Pocket to Same-Side

Ear Path Loss [dB]

Pant’s Pocket to Opposite Ear Path

Loss [dB]

Antenna Range (Free Space) 66.33 76.69

Lab Environment – Person 1 59.58 67.71

Lab Environment – Person 2 68.43 65.91

Outside, on parking structure 72.67 65.62

Large Hall 59.67 54.25

Lunchroom, sitting 70.58 76.3

Lunchroom, standing 64.55 66.57

Office, sitting 66.06 67.76

Office, standing 57.8 67.42

Small Hall 60.33 65.87

• Using a Software Radio test setup we measured the path loss for various pocket-to-ear scenarios and for different environments

• 2 different cases considered: Pant’s pocket to ear on same and opposite sides

• Path Loss computed as:

•Includes antenna losses (Note: average gain is -2dB at either end)

“Pants” pocket to opposite ear

oAntennaTxPowerInt

ofAntennaRxPowerOutPathLoss 10log10

March 2008

Slide 12

doc.: IEEE 802.15-<160r1>

Submission

Conclusions• Newly unlicensed spectrum presents an opportunity for global BAN apps

– Global “window” presently limited to 7.25GHz – 8.5GHz operation

• High frequencies enable high density and high reuse applications

• Inexpensive options exist for omni-directional antennas in 7.25-8.5GHz

• Initial tests suggest path loss performance is quite reasonable, even at higher frequencies

• Suggest 802.15.6 standards committee not preclude consideration of appropriate technology proposals for this band